Explosive projectile.



F. I. DU PONT. EXPLOSIVE PROJEGTILE.

' 1o. Patented June 20, 1911.

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FRANCIS I. DU PONT,. 0F WILMINGTON, DELAWARE.

EXPLOSIVE PROJECTILE.

Specification of Letters Patent.

Patented June 20, 1911.

Application filed September 15, 1910. Serial No. 582,167.

T o Z whom it may concern:

Be it known that I, FRANCIS I. no PONT, a citizen of the United States, residing at ll'ilmington, county of Newcastle, and State Of DOlHWRIG, have invented a new and useful Improvement in Explosive Projectiles, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, which form a part of this specification.

The object of the invention is to provide means for exploding a projectile, for instance a shrapnel shell, a given time after the same has left a gun, with greater accuracy than has heretofore been don? The invention consists in means, con trolling the firing of the detonator, whose operativeness depends upon the rotation imparted to the shell when itpasses from a cannon, which means isadapted to be rendered operative after a given number of ro-' tations' of the shell.

A preferred embodiment of my invention is shown in the accompanying drawings, in which:

Figure 1 is a longitudinal section through the projectile; Fig. 2 is an enlarged section of the casing on the line 22 of Fig. 1; and

Fig. 3 is an enlarged plan view of the nut. a is a shell with a space 6 to be filled with explosives.

c is a cap screwed into the base of the shell.

(Z is a steel casing screwed into the inwardly projecting annular flange of the cap and projecting into the space 6 of the shell.

6 is a detonator support screwed onto the end of the casing d.

f is a detonator filled with a high detonating explosive capable of detonating the explosive contained in the space I). The detonator f is supported on the end of the support 6.

g a primer, supported on the end of the support 6', whose function is .to ignite the detonating materialin thedetonator f.

h is a plunger'or hammer slidable within the cylindrical body of the support e.

z is a ring or collar secured at the lower end of the support e and through which normally extends a rod or shank, j carried by the hammer 71 and forming with. it the firing pin spring 70 is to drive forward the hammer 71-, whose point Z punctures the primer g.

The lower end of the firing pin has a knob m which is held by a holder n, which consists of two levers shaped like the two arms of a pair of pincers and, like them, pivoted near their holding ends, 0 representing the pivot pin, which is rigidly held extending recesses 1 formed in the casing and opening into the space in which the nut slides. Through the threaded central orifice of the nut extends a screw 8, which extends beyond the threadedend of the casing (Z into the space between the casing 03 and cap '0, and has there mounted upon it a flywheel t. The screw, or the extension thereof carrying the fly-wheel, turns in bearings on both the cap 0 and easing d.

lVhen a projectile passes from a cannon it is rotating at about 7000 r. p. In. This is caused by the rifling. When a projectile provided with the above described mechanism starts its flight from a cannon, all said mechanism, except the fly-wheel t and screw 8, rotates with the shell, but the flywheel, which is free to turn relatively to the shell, and Whose axis is coincident with the center-of rotation of the shell, does not get started by the force which determines the rotation of the shell, and therefore remains stationary, or nearly so, while the shell and its other contained mechanism is revolving. 'The efl'ect upon the mechanism is precisely the same as if the wheel were revolving while the other mechanism remained stationary' Hence, as soon as the projectile starts to rotate, the nut p, which at this time is at or near the upper end of of revolutions, the nut passes beyond the arms of the holder n, whereupon these-arms, by the action of the spring 70 tending to all the knob m out from the jaws of the iiolder n, and also by the centrifugal force of the rotating projectile, fly apart (their shell or at any other tilne'than during the flight of the shell. Such means is shown'in' Fig. l. o is a piston slidable within guides formed by the cap 0 and easing d. On the outer end of the piston is a gas' check w,

- which may be formed of a cup-shaped piece of copper and which is exposed, with the base of the projectile, to the firing chamber of the gun. a: is a lead pin,- swaged into both the piston and the side of. the cap 0, the pin being adapted to maintain the piston 'u in its normal position. The piston is provided, at its inner end, with a projection y, which engages a notch in the'perip'hery of the fly-wheel 25 so long as the piston'is in its normal position and thereby restrains the fly-wheel from rotation relatively to the shell. In firing the projectile, the pressure of the gases, acting upon the piston or, is sufficiently strong to deform the lead pin m and move the piston a suflicient distance to unlock the fly-wheel t.

From the foregoing description it will be understood that the time of explosion of the projectile may be regulated with great accuracy. The mechanism for exploding the projectile will bereleased when the number of rotations of the shell equals the number 'of turns of the screw 8 between the starting point of the nut 72 and the outer ends of the arms of the holder a. The distance of travel of the projectile in a single rotation of the projectile being almown factor, and the distance'traveled by the projectile in the number of rotations required to release the holder being therefore also known or readily determinable, the mechanism for exploding the shell will necessarily be released after the shell has traveled this known or determined distance. It will also be understood thatthe nut p may be adjusted on the screw 5, so as to regulate to a nicety the time of explosion. The only modifying factor necessary to consider is the possible small amount of rotation of the fly-wheel with the shell, but this factor, if not negligible, is fixed and ascertainable andwill not therefore afi'ectthe accuracy of the operation of the mechanism.

Having nowfully described my invention, what I claim and desire to protect by Letters Patent is "1. In a projectile, the combination with axis-coincident with the longitudinal center line ofthe projectile, mechanism rotatable with the projectile,,geared to the fly-wheel, and light in weight relatively thereto whereby substantially none of. the rotary movement of the projectile is imparted to the fly wheel, a' primer, and means adapted to explode the primer, geared to said mechanism and arranged to function only after/a predetermined number of revolutions of the projectile around the fly-wheel.

2. In a projectlle, the combination with the shell, of means positioned wholly. with in the shell and rotatablymountedin bearings therein'on an axiscoincident with the longitudinal center line ofthe shell, whereby, in the flight of the shell, the rotary movement thereof is. not imparted to said mechanism, other'means rotatable with the shell and gearing with the first.- named means, and firing-mechanism controlled in 1ts operation by one of said means.

3. In a pro ectile, the'combinatlon with the shell and the primer contained therein,

of a fly-wheel located entirely within theshell and freely rotatable relatively to the shell on the latters longitudinal axis, and primer-exploding means-operable by the flywheel in its relative movement of rotation.

4:. In a projectile, the combination with the shell and the primer contained therein, of a fly-wheel rotatably mountedin bearings within the shell on an axis coincident with the longitudinal center line ofthe shell, and

means, operable by; the fly-wheel, including.

gearing and aprimer exploding device. 5.111 apro ectile, the combination with gitudinal center line of the shell, whereby, in the flight of the shell the rotary movement thereof is not imparted to said mech anism, other means rotatable with the shell and gearing with the first means, and firing mechanism connected with the last named means and controlled in its operation ter thereof, means rotatable with theshell and gearing with said shaft, and firing mechanism connected with said means and, controlled in itsoperation thereby.

7; In a projectile, the combination with the shell, of means positioned wholly within the shell and rotatably mounted in bearings therein on an axis coincident "with the longitudinal center line of the shell, other means rotatable with the shell and gearing with the .first named means and movablelongitudinally of the shell, and firing mechanism connected with and controlled bythe'longitudinally movable means.

8. In a projectile, the combination with 100 "the shell, of means positioned wholly within the shell and rotatably mounted in bearings therein on an axis coincident with the lonthe shell, of a fly wheel located entirely within the shell and freely rotatable relatively to the shell on the latters longitudinal axis, normally inoperative firing mechanism, and intermediate mechanism between said fly-wheel and firing mechanism, operable by the fly wheel in its relative movement of rotation, to render said firing mechanism op-.

erative.

9. In a projectile, the combination with the shell, of firing mechanism, a fly wheel located entirely within the shell and freely rotatable relatively to the shell on the latters longitudinal axis, means normally restraining the firingmechanism from operation, and intermediate mechanism between said fly-wheel and restraining means, operable by the flywheel, in its relative movement of rotation, to render said restraining means inoperative.

10. In a projectile, the combination with the shell, of firing mechanism, a shaft arranged along the longitudinal axis of the shell, a fly-wheel on the shaft, said shaft and fly-wheel being inclosed'within the shell and free to rotate relatively to the shell,

means normally restraining the firing mechanism -from operation, and intermediate mechanism between said shaft and restraining means, operable by the shaft, in its relative movement of rotation, to render said restraining means inoperative.

11. In a projectile, the combination with the shell, of a fly-wheel and screw rotatable relatively to the shell, a firing pin, a holder normally holding said firing pin from operation, and a nut on the screw movable longitudinally thereof. and adapted to normally hold said holder in its operative position but to render said holder inoperative in the course of the travel of the nut along the screw.

12. In a projectile,-the combination with the shell, of a fly-wheel and screw rotatable relatively to the shell, a nut on the screw, a longitudinally movable firing pin, a spring tending to actuate the firing pin, a holder normally restraining said spring and pin from operation and normally locked by said nut in its operative position but adapted in the movement of the nut along the screw to be unlocked, thereby releasing said' spring and pin.

' 1 3. In a projectile, the combination with a firing pin, of a holder restraining the same from operation, said holder comprising a lurality of hinged arms, mechanism rotatabre relatively to the shell, and a nut actuated bv said mechanism having orifices through I hich said arms normally extend, whereby the arms of the holder are held in operative position until said nut moves beyond the ends of said arms.

14, In a projectile, the combination with the shell, of a detonator support, a firing pin longitudinally movable therein, a spring tending to actuate said firing pin, a holder comprising a plurality of hinged arms forming jaws at one end normally engaging said pin and holding vit-from actuation, mechanism rotatablerelatively to the shell, and a nut actuated by said mechanism having orifices'through which the other ends of said arms extend, whereby said nut holds the jaws of the holderclosed upon the pin until said nut in its travel disengages said arms.

15. In a projectile, the combination with the shell, of a casing therein having a longitudinal passage, a cap adapted to close the base of the shell, a screw extending into said passage and into the space between the casing and the cap, said screw being located substantially along the axis of rotation of the shell, a flywheel on said screw in the space between the casing and the cap, a nut on said screw and movable in the passage in the casing, and firing mechanism adapted in said movement'of the nut to be rendered operative.

16. In a projectile, the combination, with the shell, of a casing therein having a longi tudinal passage, a screw extending into said passage, a fly-wheel on the screw, the axis of said screw and fly-wheel substantially coinciding with the axis of the shell, a nut on said screw and movable in the casing, a detonator support mounted on said casing and having a longitudinal passage, a firing pin movable in said passage, :1 spring adapted to actuate said pin, and a holder engaging said nut during a part of the latters travel and adapted when so engaged to hold said spring inoperative.

17. In a projectile, the combination with the shell, of a casing therein having a longi tudinal passage and longitudinal recesses opening into said passage, a rotatable screw extending into said passage, a fly-wheel on the screw, a nut on the screw, projections on the nut extending into said recesses whereby the nut is held from rotation of the screw, and'firing mechanism adapted in said move- 'ment of the nut to be rendered operative.

18. In a projectile, the combination with the shell, of normally inoperative firing mechanism, rotatable mechanism adapted upon rotating a given number of revolution? to render said firing mechanism operative, a piston longitudinally movable in the base of the shell and normally locking said rotatable mechanism from' operation, and means normally holding said piston in locking positionbut adapted to yield to permit the piston to move to unlock said rotatable mechanism under the influence of the gases for propulsion of the shell from the gun.

19. In a projectile, the combination,with the shell, of normally inoperative firing mechanism, rotatable mechanism adapted, upon rotating a given number of revolutions the passage in.

to render said firing mechanism operative, a

piston longitudinally movable in the base of hereunto set my hand, at "ihnington, Delathe shell and normally locking said rotatable l were, on this 10th day of September, 1910. 1 niechanisni froin operation, 111d 21 deforin- FRAXCIS I. DUPOX". able pin connecting the shell and piston and normally holding the latter in locking'posi--- 'tion.

Witnesses M. M. HAMILTON, E. E. TVALL.

' Copies of this patent may be obtained for five cents each,-by addressing the Commissioner of Patents.

' Washington, D. G.

In testimony of which invention, I have 

